Problem with backlit gauge., Gives no reading with lights turned on.. Options

[Delta_Phoenix]

I've got the Auto Meter Cobalt series air/fuel gauge installed in my car. The problem I'm having is that when I turn my lights on with the gauge's illumination wire connected, the LEDs on the gauge turn off and won't give a reading. I've got the red wire (12V) connected to the cig. lighter power, the ground wire is connected to the ground wire on the cig. lighter, the illumination is connected to the cig. lighter light wire, and of course the sensor wire is connected to the O2 sensor. The gauge works fine as long as the illumination isn't hooked up, or if I have my lights off.

Anyone know what the dilly is with this gauge?

[AudioFreak]

Try connecting the illumination to the 12v directlyand see if it works. It's possible the illumination voltage isn't high enough because of the dimmer switch.